<template>
    <div class="login_container">
        <div class="login_box">
            <!-- 头像区域 -->
            <div class="avatar_box">
                <img src="../assets/logo.png" alt="">
            </div>
            <!-- 登录表单区域 -->
            <el-form ref="loginFormRef" :model="loginForm"  :rules="loginFormRules" label-width="0px" class="login_form">
                <!-- 用户名 -->
                <el-form-item prop="username">
                    <el-input v-model="loginForm.username" prefix-icon="iconfont icon-user"></el-input>
                </el-form-item>
                <!-- 密码 -->
                <el-form-item  prop="password">
                    <el-input v-model="loginForm.password" prefix-icon="iconfont icon-3702mima" type="password"></el-input>
                </el-form-item>
                <!-- 按钮区域 -->
                <el-form-item class="btns">
                    <el-button type="primary" @click="login">登录</el-button>
                    <el-button type="info" @click="resetLoginForm">重置</el-button>
                </el-form-item>
            </el-form>
        </div>
    </div>
</template>

<script>
export default {
    data(){
        return {
            //这是登录表单的数据绑定对象
            loginForm:{
                username: 'admin',
                password: '123456'
            },
            //这是表单的验证规则对象
            loginFormRules:{
                //验证用户名是否合法
                username:[
                     { required: true, message: '请输入活动名称', trigger: 'blur' },
                     { min: 3, max: 5, message: '长度在 3 到 5 个字符', trigger: 'blur' }
                ],
                //验证密码是否合法
                password:[
                    { required: true, message: '请输入活动密码', trigger: 'blur' },
                     { min: 6, max: 15, message: '长度在 6 到 15 个字符', trigger: 'blur' }
                ]
            }
        }
    },
    methods:{
        //点击重置按钮重置登陆表单
        //1给el-form的设置ref属性(ref属性的值(引用对象loginFormRef:{VueComponent})就是el-form的实例对象)
        resetLoginForm(){
            this.$refs.loginFormRef.resetFields()
        },
        //点击登录按钮在发起axios请求之前对用户提交的表单参数进行预校验
        login(){
            this.$refs.loginFormRef.validate(async valid=>{
                if(!valid) return
                var {data:res}=await this.$http.post('login',this.loginForm)
                if(res.meta.status!==200) return this.$message({showClose: true,message: res.meta.msg,type: 'error',duration:1000})
                this.$message.success({showClose: true,message: res.meta.msg,type: 'success',duration:1000})
                //1将登陆成功后服务器返回的token保存到客户端的sessionStorage中
                sessionStorage.setItem('token',res.data.token)
                //1.1项目中除了登录之外的其他接口必须在登录之后才能访问
                //1.2token只有在网页开启的时候生效,所以将token保存在sessionStorange中
                //2通过编程式导航跳转到后台主页,路由地址是/home
                this.$router.push('/home')
            })
        }
    }
}
</script>

<style lang="less" scoped>
    .login_container{
        background-color: #2b4b6b;
        height: 100%;
    }
    .login_box{
        width: 450px;
        height: 300px;
        background-color: #fff;
        border-radius: 3px;
        position: absolute;
        top: 50%;
        left: 50%;
        transform: translate(-50%,-50%);
        .avatar_box{
            width: 130px;
            height: 130px;
            border: 1px solid #eee;
            border-radius: 50%;
            padding: 10px;
            box-shadow: 0 0 10px #ddd;
            position: absolute;
            left: 50%;
            transform: translateX(-50%) translateY(-50%);
            background-color: #fff;
            img{
                width: 100%;
                height: 100%;
                border-radius: 50%;
                background-color: #eee;
            }
        }
    }

    .login_form{
        position: absolute;
        bottom: 0;
        width: 100%;
        padding: 20px;
        box-sizing: border-box;
    }

    .btns{
        display: flex;
        justify-content: flex-end;
    }
</style>